package com.wfyn.reggie.common.filter;

import com.alibaba.fastjson.JSON;
import com.wfyn.reggie.common.context.BaseContext;
import com.wfyn.reggie.common.web.domain.Result;
import com.wfyn.reggie.common.web.domain.ResultCode;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.nio.charset.StandardCharsets;

/**
 * 检查用户是否已经完成登录
 * @author wfyn
 */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter{
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();// /backend/index.html

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/user/login",
                "/user/sendMsg"
        };


        //2、判断本次请求是否需要处理
        boolean check = check(urls, requestURI);

        //3、如果不需要处理，则直接放行
        if(check){

            filterChain.doFilter(request,response);
            return;
        }

        //4、判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("employee") != null){

            Long empId = (Long) request.getSession().getAttribute("employee");

            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);
            return;
        }
        if(request.getSession().getAttribute("user") != null){
            Long userId = (Long) request.getSession().getAttribute("user");

            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }




        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        String jsonString = JSON.toJSONString(Result.failure(ResultCode.NOT_LOGIN));
        response.setCharacterEncoding("UTF-8");
        response.setContentType("application/json;charset=UTF-8");
        response.getOutputStream().write(jsonString.getBytes(StandardCharsets.UTF_8));


    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls 不需要处理的请求路径
     * @param requestURI  本次请求的URI
     * @return 检查
     */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }
}
